TED Talks"TED is a nonprofit devoted to spreading ideas, usually in the form of short, powerful talks (18 minutes or less). TED began in 1984 as a conference where Technology, Entertainment and Design converged, and today covers almost all topics — from science to business to global issues — in more than 100 languages." Summary from website.
On the other hand, TEDx events are independently run-- they are not held to the same standards, so buyer beware.